Treatment of copper alloys



. Copper Alloys Patented- '0 UNITED. TES

FRIEDRICH HE'U'SLER, or DILLENBURG,

GERMANY.

No Drawing.

To all whom it may concern.

Be, it known; that ;I,.FR1nDR1oH HEtisL'nR,

a citizen ot'the German Republic, and-re.

siding ,at Dillenburg, Germany, ,have invented certain new and useful Improvernna'rnnn'r or corrERfALLoYs."

Application filed August 29, 1921. Serial a... 496,600

. of 15%.. and then, temperature of 255 and. aluminum... Someof these alloys can.

be rolledand forged and Ihave foundv that...

the qualities of 'copper-alloys of thiskind containing from about/10 to 15% nese, and from about 7 to 10%.

limit" 7 k I cutting power, by'prolonged heating];

This invention therefore consists in treat:

ing copper alloys with manganese and tension of 9%.

um @Q t by: h at ng afa P longed" peridd to a temperature below red heat for example from about 200 to 250 C. For example an alloy consisting of from 10 to 15% manganese and from 10 to 15% aluminum, the remainder being copper when rolled, annealed and cooled in water, showed a tensile strength of 66 kg. per sq. mm. and an extension of about 21%. The same alloy when treated in the above manner and then subjected for twenty hours to a temperature of 195 showed a tensile strength of 75 kg. per sq. mm. and an ex- Again the same alloy afterbeing rolled, annealed and cooled and subjected to a temperature of 220.for'10 hours showed a tensile strength of 96 kg. per sq. mm. and an extension of 0%. ing or tempering process increases the cutting capacity of the metal so as to render the alloy particularly suitable for the manufacture of knives and more particularly of fruit lmives. v

It might be expected that this hardening process could be applied to all rolled copper alloys, but by the experiment it has'been found that copper alloys containing 13 to 14% manganese, but free from aluminum do not alter with the above treatment, neither do copper alloys containing 13% of manganese and 4 to 5% alloy containing only 5% of manganese and 9% of aluminum was found after ,of-mangav aluminum. can be. completely changed :as regards the of aluminum. A copper of elasticity andtheir; hardness and sisting This hardensame alloy treated a 1 sub ected vforv 50 hours .to a" temperature or it of 16%. ..-An alloy GERMANY, ASSIGNQR rofrn n" ISA- IBELLENHUETTE ensnmiscnanr MITJBESCIHRKNKIER HAITUNG, on mnnimnum,

a prolonged exposure-atg2551to'haveha its tensile strength very considerably in-f creased although there was no" diminution in the ex-tension. Foi' i alloyawhenyforged and: cooled from aidar'k:

example siichQariT red heat showed an elastic'li it 1 32kg,

a tensile strength of .77 kg. and

subjected an'xtension 1. sThe same'alloy similarly treated,"

for twenty hours to a showed an elastic limit from v 16 .to 50 kg.,fia tensile-strengtl1"'of 77?" kg. and a; extension of 15%. Again "the as above-"described and 1255 ,showed an elastic limitYof -50f kg 2.

kg; and an extension '11 containing"froin'etto 5%] I manganeseand onlytto 5% aluminumis" tensile strengthof that alloys free from-T man of 60.5% copper', 3 .p n lead, and 0.6% iron. or 66%'= co'pper, '3 zinc and 0.3% annealed and cooled could not tibly hardened.

be perceptotally different manner, for example a compressed manganese brass consisting .of 57.6 copper, 37.3 zinc, 2.7%--manganese and 1.2% aluminum and the remainder iron and lead can be hardened at. a tem- 'perature of 250. Such an alloy showed after annealing to 550 C. and; cooling, a Brinell hardness of 150. The samealloy after annealing and cooling as above, and after beingsubjected to heating for twenty four hours at 250 showed a hardness of 163. Again this alloy when annealed at 500 and cooled showed a Brinell hardness of 144, whereas, twenty four hours heating at 250 the hardness was 161. The same alloy after annealing at 450 and cooling, showed a Brinell' hardness of 143, but' after being subjected to 24 hours heating at 250 showed a Brinell hardness of 160.

iron, after being rolled,

when further subjected to 0 On the other hand similar alloys containing manganese behave in a The hardening effect is much more marked 2 sion of 11% and a hardness of 166. After heating for 36 hours to 230, the tensile strength was 60 kg. per sq. mm., an extension of 2% and a hardness of 260. It is also possible to harden alloys containing manganese, copper and tin. An important result, which can be obtained with the useture of 215 has a hardness of 205, and

after this treatment for 60 hours the hardness of 274.

An alloy consisting of 81% of copper, 14% manganese, 2% iron and 3% silicon cast in sand, shows a hardness of 117, and after exposure for 36 hours at a temperature of 215 has a hardness of 152, and after this treatment for 96 hours, the hardness was 174.

An alloy consisting of 80.6% of copper, 15% manganese,-1% iron and 3.4% silicon, after being forged and annealed at 600 and cooled, has a hardness of 178, and after exposure for 36 hours at a temperature of 215 the hardness of 249.

An alloy consisting of 77% of copper,

14% manganese, 3% iron and 6% silicon, cast in sand, shows a hardness of 170, and after exposure for 24 hours at a temperature of 215 has a hardness of 222, and after this treatment for 60 hours, the hardness was 220.

The essential feature of this invention is not afi'ected by the addition of other metals to the alloys described above, for example iron, nickel, cadmium or lead may be present. The presence of such additions only affects the hardening temperature and in some cases makes the alloys more easily cast.

Now what I claim is:

1. The method of increasing the hardness and elastic limit of alloys containing .a predominant proportion of copper and relatively small proportions of mangan$e and aluminum which consists in subjecting the alloys after the have been cast, rolled or forged, to a pro onged heatingrtreatment at a temperature of approximately 200 C. to 250 C.

. 2. The method of increasing the hardness and elastic limit of alloys containing a predominant proportion of copper and approximately 10% to 15% manganese, together with approximately 7% to 10% aluminum which consists in subjecting the alloys, after they have been cast, rolled or forged, to a prolonged heating treatment at a temperature of approximately 200 C. to 250 C.

In testimony whereof I have affixed my signature.

DR. FRIEDRICH HEUSLER. 

